In their first 10 league games, Southampton conceded 28 goals. In their last six they have conceded four, picked up 11 points and climbed out of the relegation zone. Analysis of the Saints' recent improvement does not start and end there – the quality of their opponents in those first 10 games was noticeably high – but Nigel Adkins accepts that having a settled back four has been a major factor.

"Defensively we're more resolute," acknowledged the Southampton manager, singling out the teenage left-back Luke Shaw. Quick and strong, the 17-year-old is already being likened to a previous occupant of his position in Gareth Bale – and inevitably being touted as a January transfer target of clubs including Arsenal and Chelsea – but the right-back Nathaniel Clyne was at least equally impressive. Both showed notable pace, stamina and, crucially, timing in getting forward, while the centre-backs José Fonte and Maya Yoshida kept Reading strikers Jason Roberts and Adam Le Fondre very quiet.

Indeed it was Clyne, with an intelligent inside ball, who created the chance for Jason Puncheon to score the winner, shortly after the hour, and they never really looked like conceding thereafter.

"I think it was nerves, to be honest," said Puncheon, when asked why Southampton are beginning to look so much more secure at the back. "As a team coming into the Premier League we were all a bit nervous, a bit shaky. We need to find our feet, our rhythm, and we're beginning to do that now."

Not least Puncheon himself, whose rehabilitation in the Southampton team after a period when it seemed only a matter of time before he was moved on is as much a tribute to Adkins as to the player. The Londoner spent much of last season training with the juniors and out on loan after a public spat with the chairman, Nicola Cortese, but he has now scored three Premier League goals this term.

"We're demanding of people but we're also supportive," said Adkins. "People have to fit in but we treat them as human beings; they have to be allowed to make mistakes and grow. He's matured as a person and as a footballer, so all credit to him."

The goal should have been Puncheon's second after he headed in Adam Lallana's first-half corner, an effort that was ruled out for a non-existent foul by Yoshida.

Hal Robson-Kanu did head against a post for the Royals shortly before half-time, and Jay Tabb was unlucky not to win a penalty after being tripped by Jack Cork, but those were rare moments of hope for Brian McDermott's side.

The Reading manager was subdued afterwards and it may be as well the Royals have no time to dwell on their performance. While Southampton could enjoy their club Christmas party, Reading trained in preparation for Tuesday's trip to Sunderland. As McDermott acknowledged, the game is even more significant with Sunderland having fallen into the bottom three.

"We're particularly disappointed because we didn't really get the response we needed when we went 1-0 down, which we always get," said McDermott. "I haven't had many bad days over the last three years but that was one.

"Our form at the Madjeski Stadium is going to be really, really important but you have to pick up points away from home as well. After every defeat you're down but now we have to go to Sunderland and make sure we're difficult to play against and get a result."

Southampton play Sunderland next, too, but not until the Saturday before Christmas, as next weekend's scheduled opponents, Chelsea, will be in Japan for the Club World Championship. It gives them a useful opportunity to work on the condition of Lallana, who left the ground with a knee in a precautionary brace after limping off in the first half.